Tweaking graphics in rFactor 2

I made some weathers and pp-filters in assetto corsa. I guess rFactor doesnt have available ini-files where we can as easily create filters and so on for sharing in rFactor..

But how do one go about tweaking and making graphical and weather mods in rFactor2? I would very much like some information or if someone could point me in the right direction. I think it has some potential if someone really dug in and tweaked some stuff around.

I guess I could use SweetFX heavily but that would probably cause a dramatic fps hit.